1. Field of the Invention
This invention relates generally to sealing arrangements and method of making same, and more particularly, sealing arrangements for heated chambers and methods for sealing same.
It is well known especially from Environmental Reports and the news media that the sealing of ovens which produce noxious fumes, smoke, dust, etc., is a difficult art. Only recently the coke industry in the major steel producing area of the United States has been threatened with a complete shutdown because of its inability to comply with the new Environmental Regulations of the Environmental Protection Agency of the U.S. of America and the Department of Environmental Resources of the Commonwealth of Pennsylvania.
An example of a coke oven which presently has sealing problems, is a coke oven with a so-called Koppers Door. The coke oven with the Koppers Door utilizes an S-shaped seal for sealing the door against the jamb of the oven. Because of irregularities in the jamb and seal, gases from within the coke oven readily leak past the jamb. In cases where the seal surfaces have been damaged by loading and unloading of coal and coke, gouges occur therein, which greatly increase the flow of noxious gases and fumes from the coke oven to the surrounding air. This leakage from damaged ovens is especially undesirable since the degree of pollution caused thereby is many fold that of an oven in preferred condition. However, during long use coke ovens are damaged by the constant loading and unloading and seal cleaning, therefore, a larger and larger percentage of the ovens leak at ever increasing rates.
Another door widely used in the coke industry is the Wilputte Door. The Wilputte Door has a diaphragm seal and a jamb with an adjustable screw for making contact more readily between the jamb and the door. The Wilputte Door also suffers from the same sort of problems that the Koppers Door does. A great need is also felt for an imporved sealing arrangement therein.
Recent tests have shown that many of these doors in present operation in their present configurations do not permit operation within the guidelines set by the Department of Environmental Resources and the Environmental Protection Agency. The fact of the lack of capability of meeting these requirements is well known and has threatened to shut down the steel industry for lack of coke. Therefore, a great need is felt for an improved door sealing arrangement which would permit operation within the guidelines of the Environmental Protection Agency or the Department of Environmental Resources.
There are a great number of other applications where leakage from ovens and other heated chambers can be cured by use of my invention such as soaking pits, used for the soaking of iron ingots during the manufacture of iron and steel, furnaces and other examples which are too numerous to mention herein.
2. Description of the Prior Art and Results of Novelty Search
A means of attempting to seal a coke oven is disclosed in U.S. Pat. No. 3,875,018 to Calderon in which a collodial mixture is injected into a passage from which it leaks out in such a way that during the coking cycle the mixture becomes gummy and sticky for sealing crevices between the door and the jamb. The mixture dehydrates and develops non-wetting and non-adhering properties by hardening into a strong solid mass. This method requires a special door design which incorporated channels for receiving the mixture. Problems have been discovered in the injection of the mixture into the channel because the mixture has a tendency to leak out of the channel and past the seal before it has an opportunity to harden sufficiently.
The novelty search conducted prior to the preparation of this application turned up U.S. Pat. No. 2,279,791, which only teaches the application of the material which expands when subjected to elevated temperatures. This material is used to coat the individual wires of a fire screen. The fire screen thus coated, when exposed to elevated temperatures causes the material to expand. The expansion closes the openings between the individual wires of the screen, thereby restricting the flow of air at elevated temperatures through the fire screen.
Another result of the novelty search is U.S. Pat. No. 3,814,613 which discloses the use of a refractory composition for patching the walls of a coke oven. This refractory composition comprises siliceous aggregate, plastic clay, a chemical binder such as sodium silicate, chromic acid, boric acid, sodium sulfate, magnesium sulfate, sodium phosphate and organic binders and finally, a source of manganese dioxide. The patching material may be applied by the troweling or plastering over a cracked area in the wall of the coke oven or by pumping or injecting the material into cracks in the wall or by pneumatically gunning. This patent has the object of providing a patching material for coke ovens which has a long lasting bond with used silica brick.